Intel's 90nm Pentium M 755: Dothan Investigated
by Anand Lal Shimpi on July 21, 2004 12:05 AM EST- Posted in
- CPUs
Dothan's Model Numbers
Intel started their model numbering system with Dothan's launch. For those of you who are confused by the "helpful" system, here is a table to tell you at what clock speeds the various processors are really running:| Core | Clock Speed | Thermal Design Power | |
| Intel Pentium M 755 | Dothan | 2.0GHz | 21W |
| Intel Pentium M 745 | Dothan | 1.8GHz | 21W |
| Intel Pentium M 735 | Dothan | 1.7GHz | 21W |
| Intel Pentium M 733 | Dothan Ultra Low Volt | 1.1GHz | 5W |
| Intel Pentium M 725 | Dothan | 1.6GHz | 21W |
| Intel Pentium M 723 | Dothan Ultra Low Volt | 1.0GHz | 5W |
| Intel Pentium M 715 | Dothan | 1.5GHz | 21W |
| Intel Pentium M 713 | Banias Ultra Low Volt | 1.1GHz | 7W |
| Intel Pentium M 705 | Banias | 1.5GHz | 24.5W |
For the most part, a higher number means a faster processor when it comes to the Pentium M, but there are a few exceptions.
First of all, the 715, 725, 735 and 745 all have one thing in common - for every 10-point increase in model number, there is a 100MHz increase in clock speed. The 755 is the only exception, which has a 10-point increase in model number for a 200MHz increase in clock speed.
The 705 runs at the same speed as the 715, but it uses the older Banias core - so that's a chip that you'll want to stay away from as it offers lower performance and is more power hungry.
The Ultra Low Voltage Dothans run at 1 - 1.1GHz, but have model numbers close to that of the 1.6GHz and 1.7GHz Dothans. Although they consume far less power, keep in mind that they will not perform similarly to the 725 and 735 processors. Then again, these chips are normally found in ultra portable notebooks that wouldn't offer normal Pentium M chips, so it's not usually a decision that you'll have to face. If you want an ultra portable, you'll have to put up with lower clocked processors.
Looking at the TDP values, you see that clock for clock, Banias consumes more power than Dothan, making Dothan better for performance and battery life. For those who look at Prescott as an example of how "bad" Intel's 90nm process is, take a look at Dothan as a more accurate measurement. Without any architectural changes, 90nm allows Dothan to run cooler and faster - the opposite of what we've seen on Prescott, leading us to believe that the reason for Prescott's heat issues isn't Intel's 90nm process, but rather the architectural changes to Prescott.
Facebook
Twitter
RSS
28 Comments
View All Comments
nserra - Wednesday, July 21, 2004 - link
#3 I agree. Banias is a better chip. It would be nice to see Banias at 0.09 with 1MB cache, would be smaller, cheaper and a lot more chips per waffer, but Intel isn't interested in these yet, at least maybe a Celeron line when Banias phased out.Isn't Ati 9100 chipset compatible with Banias and P4 compatible? A bios change or something more wouldn’t do the trick?
Matthew Daws - Wednesday, July 21, 2004 - link
Interesting read. Some comments though: the Dothan has a HUGE L2 cache, which people, in a thread over at Ace's, suggest gives it a large edge in many applications (there were complaints that it excels in SpecInt simply because of this, and with very large datasets, performance rapidly tails off). Nothing wrong with that, but it might explain why the Dothan has issues with media-encoding and the like, where the volume of data is so large that the size of the L2 cache becomes less important.Also, the test was a little bit of comparing apples to oranges. I see why this was done: to try and give a laptop-like playing field. But Dothan is almost certainly highly optimised to run with, say, single channel, slow RAM. By forcing this on Athlon64 and Pentium 4 desktops, which are optimised for fatter memory channels, you are slightly crippling performance. As such, it's probably a fair test for laptop performance, but probably doesn't indicate how a Dothan-like desktop chip would hold up. This might explain how well it holds its own against the Athlon64 and beats the P4 in many tests.
Anyhow, good to see a great test of Dothan! Cheers, --Matt
xsilver - Wednesday, July 21, 2004 - link
Just a question... I thought the new sucessor to the prescott was going to be the derivative of the dothan -- eg merging back the mobile and desktop solutions? I'm wrong right? So what exactly are they going to replace prescott with?morcegovermelho - Wednesday, July 21, 2004 - link
Where are the Athlon 64 3000+ scores in Sysmark 2004? (page 8)DigitalDivine - Wednesday, July 21, 2004 - link
interesting to see that we are going back to the old days when intel and amd matches each other clock for clock. a 1.8ghz centrino about the same as a 1.8ghz athlon64.still another note that the p4 is still king in media encoding.
overall a nice review.
adntaylor - Wednesday, July 21, 2004 - link
Excellent chip. However, it's bloody expensive. At $637 it is exactly the same price as a 3.6GHz Prescott 560 or right between Athlon 64 3500+ and 3700+, so it's not a good choice for the desktop.Also Anand's comment "...it's faster and uses less power than Banias" is not quite accurate.
Under full CPU load, yes this is certainly true but, as you'd expect from 90nm, the leakage power has shot right up, meaning that in its low power states, the CPU is draining a great deal more power than Banias. How much time does a laptop spend idling relative to flat out? My guess: quite a bit. I'd still choose a Banias in my laptop for that reason alone.
Still good article, and I'd love (from a purely academic point of view) to see what this baby could do when coupled up with a dual-channel memory interface and a good desktop chipset!
sprockkets - Wednesday, July 21, 2004 - link
Probably the best heat vs. performance processor out there, at least for x86. Why Intel is dumb to shove Prescotts which use 5x more power for the same performance is beyond me; I would get this for a desktop quicklike.Of course, we have Intel's TDP instead of what the processor may acutally put out on worst case conditions. That and we don't know what the Athlon 64 at 90nm will put out, at least at 2.0ghz, since all they are doing is a few tweaks to the core (isn't it smaller than 100mm?) That and I guess if you really meant unpatented, that was what to make sure no one really knows why it's so great?
mkruer - Wednesday, July 21, 2004 - link
I’m glad that Intel seem to be moving in the right direction with the Dothan, but I do have a question. Why on half the benchmarks is the Athlon benchmarks missing?